Cardiovascular System
list the four chambers of the heart; specify whether the chamber is part of the systemic or pulmonary circuit
right atrium and left ventricle (systemic) and left atrium and right ventricle (pulmonary)
describe the three layers of the heart wall
epicardium: visceral layer of the serous pericardium
myocardium: contractile cardiac muscle cells
endocardium: innermost layer, continuous with endothelial lining of blood vessels
how does the autonomic nervous system affect heart rate?
sympathetic speeds up
parasympathetic slows down
list (3) differences between veins and arteries, including direction of blood flow
veins have valves while arteries do not
arteries have a thicker tunica media
arteries take blood away from the heart whereas veins take blood toward the heart
list the three parts of the lymphatic system
lymphatic vessels, lymph, lymphoid tissues and organs
describe the pericardium
superficial fibrous pericardium: functions to protect and anchor the heart to surrounding structures and prevent overfilling
deep two-layered serous pericardium: two layers separated by fluid-filled pericardial cavity
- parietal layer lines internal surface of fibrous pericardium
- visceral layer (epicardium) on external surface of heart
name the (2) structures responsible for anchoring the atrioventricular valves
papillary muscles and chordae tendineae
list the three parts of the action potential
1. pacemaker potential
2. depolarization
3. repolarization
slides 55-59
describe the three types of capillaries and where they may be found
continuous (skin, muscle), fenestrated (kidneys, SI), sinusoidal (liver, spleen, bone marrow)
describe how the structure of the lymphatic vessels is suited to their functions, including valve structure
slide 5
describe cardiac output and (2) factors that may affect it
Volume of blood pumped by each ventricle in 1 minute
CO = heart rate (HR) × stroke volume (SV)
–HR = number of beats per minute
–SV = volume of blood pumped out by one ventricle with each beat
Factors affecting CO:
1. regulation of stroke volume
2. regulation of heart rate
slides 99-113
describe the (3) major mechanical phases of the heart and during what stage of systole or diastole the phases take place
1. ventricular filling (mid-to-late diastole)
2. ventricular emptying (systole)
2a. isovolumetric contraction phase
2b. ejection phase
3. isovolumetric relaxation (early diastole)
slides 91-93
describe how depolarization and repolarization relate to: emptying and filling of the heart chambers, contraction and relaxation of the heart, systole and diastole
depolarization: contraction, emptying, systole
repolarization: relaxation, filling, diastole
describe the function of precapillary sphincters
slide 7
describe (3) ways that lymph to moves toward the heart
movement of skeletal muscles
pulmonary pressure which creates suction and prevents backflow
contraction of smooth muscle in the lymphatic vessels
describe circulation through the heart, beginning from the venae cavae emptying into the receiving chamber, including the valves
right atrium > tricuspid valve > right ventricle > pulmonary semilunar valve > pulmonary trunk > lungs > left atrium > bicuspid valve > left ventricle > aortic semilunar valve > aorta
slide 33
describe (2) differences and (2) similarities between cardiac muscle cells and skeletal muscle cells and (2) general facts about the cardiac muscle fibers
Cardiac muscle cells: striated, short, (bifurcated) branched, fat, interconnected
–One central nucleus (at most, 2 nuclei)
–Contain numerous large mitochondria (25–35% of cell volume)
–Sarcomeres
--Z discs, A bands, and I bands all present
–T tubules are wider, but less numerous
--Enter cell only once at Z disc
–SR simpler than in skeletal muscle; no triads
Intercalated discs are connecting junctions between cardiac cells that contain:
–Desmosomes: hold cells together; prevent cells from separating during contraction
–Gap junctions: allow ions to pass from cell to cell; electrically couple adjacent cells
--Allows heart to be a functional syncytium, a single coordinated unit
Similarities with skeletal muscle:
–Muscle contraction is preceded by depolarizing action potential
–Depolarization wave travels down T tubules; causes sarcoplasmic reticulum (SR) to release Ca2+
‒Excitation-contraction coupling occurs
--Ca2+ binds troponin causing filaments to slide
Differences between cardiac and skeletal muscle:
–Some cardiac muscle cells are self-excitable (built-in nervous system)
slides 43-52
list the (5) steps in the sequence of excitation in the cardiac intrinsic conduction system
1. SA node
2. AV node
3. AV bundle
4. right and left bundle branches
5. Purkinje fibers
slides 60-67
describe how blood pressure may be increased or decreased in response to homeostatic imbalance
slide 18-19
describe T and B lymphocytes
•T-cells (T-lymphocytes)
--Manage the immune response, some attacking the disease directly
•B-cells (B-lymphocytes)
--Produce Plasma Cells (can divide and become plasma cells), secreting antibodies to immobilize antigens which can then be phagocytized
describe coronary circulation, including (1) general fact, (2) facts about the coronary arteries, and (2) facts about the coronary veins
general facts:
–Functional blood supply to heart muscle itself
–Shortest circulation in body
–Delivered when heart is relaxed
–Left ventricle receives most of coronary blood supply
coronary arteries:
–Both left and right coronary arteries arise from base of aorta and supply arterial blood to heart
–Both encircle heart in coronary sulcus
–Branching of coronary arteries varies among individuals
–Arteries contain many anastomoses (junctions)
--Provide additional routes for blood delivery
--Cannot compensate for coronary artery occlusion
–Heart receives 1/20th of body’s blood supply
–Left coronary artery supplies interventricular septum, anterior ventricular walls, left atrium, and posterior wall of left ventricle; has two branches:
--Anterior interventricular artery
--Circumflex artery
–Right coronary artery supplies right atrium and most of right ventricle; has two branches:
--Right marginal artery
--Posterior interventricular artery
coronary veins:
–Cardiac veins collect blood from capillary beds
–Coronary sinus empties into right atrium; formed by merging cardiac veins
--Great cardiac vein of anterior interventricular sulcus
--Middle cardiac vein in posterior interventricular sulcus
--Small cardiac vein from inferior margin
–Several anterior cardiac veins empty directly into right atrium anteriorly
slides 36-41
describe congestive heart failure in terms of the type of condition it is its (4) potential causes
Congestive heart failure (CHF):
–Progressive condition; CO is so low that blood circulation is inadequate to meet tissue needs
–Reflects weakened myocardium caused by:
--coronary atherosclerosis
--persistent high blood pressure
--multiple myocardial infarcts
--dilated cardiomyopathy
slides 117-119
describe the main features of the Electrocardiogram
–P wave: depolarization of SA node and atria
–QRS complex: ventricular depolarization and atrial repolarization
–T wave: ventricular repolarization
–P-R interval: beginning of atrial excitation to beginning of ventricular excitation
–S-T segment: entire ventricular myocardium depolarized
–Q-T interval: beginning of ventricular depolarization through ventricular repolarization
slides 76-83
describe hydrostatic pressure, osmotic pressure, how they relate to blood pressure, and under what conditions fluid will move both in and out
slide 27
describe circulation through the lymph nodes and how the structure of the lymph nodes aid in circulation
slides 20-22